Morphology and systematic position of some Anomalinid foraminifera

Abstract

Morphological studies of the following species are the basis for a partial revision of the Family Anomalinadae: Anomalina acuta Plummer, A. midwayensis (Plummer), A. pseudopapillosa Carsey, A. vulgaris (Plummer), Anomalinoides pinguis (Jennings), Cibicides alleni (Plummer), C. beaumontianus (d’Orbigny), c. harperi (Sandidge), Cibicidina danvillensis (Howe and Wallace), Planulina correcta (Carsey), and P. dumblei (Applin); a description of Stensioina americana Cushman and Dorsey, discorbid foraminifer, is included for comparison. The classificatory position and incomplete content of the family are: Superfamily Discorbidea; Family Anomalinidae; Subfamily Anomalininae (revised) -- with ventral supplementary apertures: Anomalina , Planulina ; Subfamily Cibicidinae -- with dorsal supplementary apertures: Cibicides , Cibicidina , Anomalinoides . The anomalinid wall consists of radially crystalline calcium carbonate, deposited in successive enveloping lamellae, characteristic for the superfamily. In detail, the basic structure of the anomalinid and discorbid wall consists of (1) external and internal chitinoid films that also line the pores; (2) the lamellar calcareous wall; and (3) a black line within the septum and varyingly within the outer wall, composed of organic and calcareous particles. Mural pores are large, but of variable size, in the Anomalinidae; in pores large enough for the details to be seen, each is covered by a finely perforate sieve plate, near its external opening. Specific contributions of this report are: (1) emendation of the Anomalininae; (2) confirming presence of supplementary apertures in Anomalina and Planulina ; (3) transfer of Anomalinoides to the Cibicidinae; (4) synonymizing Gavelinella with Anomalina ; (5) transfer of Cibicides vulgaris to Anomalina ; (6) discovery of the detailed wall structure in anomalinid and discorbid species; (7) recognition of sieve plates in the Anomalinidae; and (8) recognition that Hofker’s “deuteropores” are simply large pores with contained sieve plates --Abstract, pages 1-2

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